Work continues on each of the three problem areas outlined in the original grant proposal. Studies aimed at unravelling the effects of the interaction between linkage and fertility selection at two-loci will be carried out. The effect of self-fertilization and natural selection in combination with linkage is also under study and will be related to data from geographically subdivided plant populations. A new project involves the construction and analysis of two-locus kin selection models. We are pursuing our studies of the interaction of genetic and cultural transmission especially as they interact with assortative mating. We have obtaind data sets that allow testing of our ideas on the change in marital correlations over time. The theory of kin selection will be extended to include multiple alleles at one locus. We plan to use our population genetic treatment in considering new models of parent-offspring conflict and the evolution of genes which affect sex determination.